Jordan Yuanzhi Li

Circulating microRNA expression is reduced in chronic kidney disease

BACKGROUND MicroRNAs (miRNAs) are important regulators of gene expression, which have roles in renal development and disease. They exist in biological fluids including blood and urine and may have signalling roles and potential as disease biomarkers. METHODS We measured the levels of miRNAs in patients with different stages of chronic kidney failure including those receiving maintenance haemodialysis treatment. RESULTS In patients with severe chronic renal failure, circulating levels of total and specific miRNAs are reduced in comparison to patients with mild renal impairment or normal renal function. A strong correlation exists between detected circulating miRNAs and estimated glomerular filtration rate, and less strong correlations with other features of chronic kidney disease, such as anaemia and hyperparathyroidism. CONCLUSION These findings have important implications for the use of circulating miRNAs as biomarkers in individuals with renal impairment and for the pathogenesis of uraemia.

The role of microRNAs in kidney disease

MicroRNAs (miRNAs) are short non‐coding RNAs that modulate physiological and pathological processes by inhibiting target gene expression via blockade of protein translation or by inducing mRNA degradation. These miRNAs potentially regulate the expression of thousands of proteins. As a result, miRNAs have emerged rapidly as a major new area of biomedical research with relevance to kidney disease. MiRNA expression has been shown to differ between the kidney and other organs as well as between different kidney regions. Furthermore, miRNAs have been found to be functionally important in models of podocyte development, diabetic nephropathy and polycystic kidney disease. Of particular interest, podocyte‐specific deletion of Dicer, a key enzyme in the biogenesis of miRNA, results in proteinuria and severe renal impairment in mice. One miRNA (miR‐192) can also act as an effector of transforming growth factor‐β activity in the high‐glucose environment of diabetic nephropathy. Differential expression of miRNAs has been reported in kidney allograft rejection. It is anticipated that future studies involving miRNAs will generate new insights into the complex pathophysiology underlying various kidney diseases, generate diagnostic biomarkers and might be of value as therapeutic targets for progressive kidney diseases. The purpose of this review is to highlight key miRNA developments in kidney diseases and how this might influence the diagnosis and management of patients with kidney disease in the future.

Successful control of Scedosporium prolificans septic arthritis and probable osteomyelitis without radical surgery in a long-term renal transplant recipient

Abstract: Scedosporium species are increasingly isolated from immunocompromised and immunocompetent patients. Scedosporium infections are generally resistant to multiple antifungals, and Scedosporium prolificans is particularly resistant to all single antifungal agents currently in use with in vitro testing. We report here a long‐term renal transplant recipient who developed isolated S. prolificans septic monoarthritis and probable osteomyelitis. The infection was successfully treated with a combination of voriconazole and terbinafine in addition to joint washout but did not require radical surgery. This combination has been shown to have synergistic in vitro effect, and anecdotal in vivo success has also been reported recently. We also review the clinical presentation, treatment, and outcome of S. prolificans infection in patients with solid organ transplantation.

Medication prescription among elderly patients admitted through an acute assessment unit

Aim:  This study assessed medication use patterns and polypharmacy in patients who were admitted through an acute assessment unit (AAU) and stratified results according to patient age. This study also examined risk factors associated with polypharmacy and consequences of polypharmacy, namely prescription writing errors, drug–drug interaction and geriatric syndrome.

MicroRNAs: are they the missing link between hypoxia and pre-eclampsia?

Pre-eclampsia is a multisystem disorder that occurs in the second half of pregnancy affecting 5% of pregnancies. It remains the leading cause of maternal and perinatal mortality and morbidity worldwide. Impaired placental implantation, hypoxia, endothelial dysfunction and systemic inflammation are thought to have a role in the pathogenesis of pre-eclampsia. MicroRNAs (miRNAs) are short non-coding RNAs. They are important regulators of gene expression and have been found to affect cell development, proliferation, differentiation and function. Specific patterns of miRNAs have been detected in the placenta and there is altered miRNA expression in the placenta of patients with pre-eclampsia to but their role in the pathogenesis remains unclear. Furthermore, deregulated miRNAs have also been reported in human villous trophoblasts during hypoxic stress. One of the more consistently elevated miRNAs by hypoxia and in the placenta of patients with pre-eclampsia is miR-210. Whether such miRNAs are bystander markers of hypoxia, or are directly involved in the pathogenesis of pre-eclampsia, needs to be clarified. There is potential for miRNAs to be used as predictors, markers or therapy in pre-eclampsia. This review provides current knowledge about miRNAs, particularly hypoxia-related miRNAs and the interaction of hypoxia, miRNAs and placenta in pre-eclampsia.

Identifying risk factors and patterns for unplanned readmission to a general medical service.

OBJECTIVE To identify factors and patterns associated with 7- and 28-day readmission for general medicine patients at a tertiary public hospital. METHODS A retrospective observational study was conducted using an administrative database at a general medicine service in a tertiary public hospital between 1 January 2007 and 31 December 2011. Demographic and clinical factors, as well as readmission patterns, were evaluated for the association with 7- and 28-day readmission. RESULTS The study cohort included 13 802 patients and the 28-day readmission rate was 10.9%. In multivariate analysis, longer hospital stay of the index admission (adjusted relative risk (ARR) 1.34), Charlson index ≥ 3 (ARR 1.28), discharge against medical advice (ARR 1.87), active malignancy (ARR 1.83), cardiac failure (ARR 1.48) and incomplete discharge summaries (ARR 1.61) were independently associated with increased risk of 28-day readmission. Patients with diseases of the respiratory system, neurological or genitourinary disease, injury and unclassifiable conditions were likely to be readmitted within 7 days. Patients with circulatory and respiratory disease were likely to be readmitted with the same system diagnosis. CONCLUSION Readmission of general medicine patients within 28 days is relatively common and is associated with clinical factors and patterns. Identification of these risk factors and patterns will enable the interventions to reduce potentially preventable readmissions.

BK Virus Encoded MicroRNAs Are Present in Blood of Renal Transplant Recipients With BK Viral Nephropathy

BK viral infection is an important cause of renal transplant dysfunction and failure. Current strategies utilize surveillance for infection with DNA polymerase chain reaction assays and modulation of immunosuppression. Many viruses including polyomaviruses encode microRNAs (miRNAs). We have detected BK virus (BKV) encoded miRNAs in the blood of infected renal transplant recipients, and see a strong correlation between BKV encoded miRNA and BKV DNA in blood and a relationship between levels of bkv‐miR‐B1‐5p and the presence of biopsy‐proven BK viral nephropathy. Further research is needed to determine whether the detection of this and other virally encoded miRNAs may be useful in the diagnosis of active viral replication.

Predicting admission of patients by their presentation to the emergency department.

The present study aims to determine the importance of certain factors in predicting the need of hospital admission for a patient in the ED.

Transitional cell carcinoma in a renal allograft with BK nephropathy.

J.Y.Z. Li, D. Fang, T.Y. Yong, S. Klebe, R. Juneja, J.M. Gleadle. Transitional cell carcinoma in a renal allograft with BK nephropathy. Transpl Infect Dis 2013: 15: E270–E272. All rights reserved J.Y.Z. Li, D. Fang, T.Y. Yong, S. Klebe, R. Juneja, J.M. Gleadle Department of Nephrology, Flinders Medical Centre, Adelaide, South Australia, Australia, Faculty of Health Science, Flinders University, Adelaide, South Australia, Australia, Department of General Medicine, Flinders Medical Centre, Adelaide, South Australia, Australia, Department of Pathology, Flinders Medical Centre, Adelaide, South Australia, Australia

Visual deterioration caused by vitamin A deficiency in patients after bariatric surgery

Vitamin A deficiency (VAD) after bariatric surgery is recognised as a significant post-operative complication that can lead to visual impairment. We report two cases of night blindness and visual impairment caused by VAD after malabsorptive bariatric surgery. Both patients were treated with intramuscular vitamin A replacement and made near complete recovery in their vision. Ocular complications due to VAD should be diagnosed and treated promptly in patients after bariatric surgery because these complications are reversible.